You are correct. I did not read the op carefully.Don't listen to those other guys; they've gone off into the weeds. The DC-resistance is related to the DC-load line used to bias an amplifier stage. The AC resistance is related to the AC load line. The DC load and the AC load are different so the load lines are different and so on.
Read the following article carefully
http://eee24h.blogspot.com/2011/04/dc-and-ac-load-line_30.html